mysql多表整合查询例子

SELECT e.stu_no as stuNo ,e.estimation_id as estimationId,
(select IFNULL(weight,0)  from evaluation_type where evalution_method_id=1  and estimation_id=e.estimation_id) as zp,
(select IFNULL(weight,0)  from evaluation_type where evalution_method_id=2  and estimation_id=e.estimation_id) as hp,
(select IFNULL(weight,0)  from evaluation_type where evalution_method_id=3  and estimation_id=e.estimation_id) as bzrpf,
(select evaluation_value  from tb_evaluation where evaluation_method=1 and stu_no=e.stu_no and estimation_id=e.estimation_id) as selfAssessment
,(select AVG(evaluation_value)  from tb_evaluation where evaluation_method=2 and stu_no=e.stu_no and estimation_id=e.estimation_id) as avgMutual,
(select AVG(evaluation_value)  from tb_evaluation where evaluation_method=3 and stu_no=e.stu_no and estimation_id=e.estimation_id) as avgTeacherAssessment,gs.name as stuName,gg.name as gradeName,gc.name as className FROM `tb_evaluation` e LEFT JOIN general_student gs on e.stu_no=gs.student_no
LEFT JOIN general_grade gg on gs.grade_id=gg.id  LEFT JOIN general_class gc on gs.class_id=gc.id GROUP BY  e.stu_no , e.estimation_id